U.S. patent application number 16/324081 was filed with the patent office on 2019-06-13 for light-source system and projection device.
The applicant listed for this patent is APPOTRONICS CORPORATION LIMITED. Invention is credited to Zuqiang GUO, Fei HU, Yi LI.
Application Number | 20190179220 16/324081 |
Document ID | / |
Family ID | 61162586 |
Filed Date | 2019-06-13 |
United States Patent
Application |
20190179220 |
Kind Code |
A1 |
HU; Fei ; et al. |
June 13, 2019 |
LIGHT-SOURCE SYSTEM AND PROJECTION DEVICE
Abstract
Provided is a light-source system, comprising excitation light
source, first supplementary light source, first light-guiding
assembly, wavelength conversion apparatus, and second light-guiding
assembly. The excitation light source is for emitting excitation
light; the first supplementary light source is for emitting first
supplementary light. The first light-guiding assembly is for
guiding the excitation light to the wavelength conversion
apparatus. The wavelength conversion apparatus is for converting
excitation light to excited light and irradiate onto the first
light-guiding assembly. The first light-guiding assembly is for
guiding excited light to irradiate onto the second light-guiding
assembly. At least some components of the second light-guiding
assembly are arranged on the light path from the first
light-guiding assembly. The second light-guiding assembly is for
guiding the excited light and/or the first supplementary light,
such that the first supplementary light and at least part of the
excited light are output from same emission channel.
Inventors: |
HU; Fei; (Shenzhen, CN)
; GUO; Zuqiang; (Shenzhen, CN) ; LI; Yi;
(Shenzhen, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
APPOTRONICS CORPORATION LIMITED |
Shenzhen, Guangdong |
|
CN |
|
|
Family ID: |
61162586 |
Appl. No.: |
16/324081 |
Filed: |
April 21, 2017 |
PCT Filed: |
April 21, 2017 |
PCT NO: |
PCT/CN2017/081490 |
371 Date: |
February 7, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 26/008 20130101;
G03B 21/2013 20130101; G03B 21/2073 20130101; G03B 21/204 20130101;
G03B 33/08 20130101; G03B 21/206 20130101; G03B 21/2033 20130101;
G03B 21/20 20130101; G03B 21/2066 20130101 |
International
Class: |
G03B 21/20 20060101
G03B021/20; G02B 26/00 20060101 G02B026/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 9, 2016 |
CN |
201610649657.X |
Claims
1. A light source system, comprising an excitation light source, a
first supplementary light source, a first light-guiding assembly, a
wavelength conversion apparatus, and a second light-guiding
assembly, wherein: the excitation light source is configured to
emit excitation light; the first supplementary light source is
configured to emit first supplementary light; the first
light-guiding assembly is configured to guide the excitation light
to the wavelength conversion apparatus; the wavelength conversion
apparatus is configured to convert the excitation light to excited
light and emit the excited light to the first light-guiding
assembly; the first light-guiding assembly is further configured to
guide the excited light, so that the excited light irradiate onto
the second light-guiding assembly; at least some components of the
second light-guiding assembly are disposed in a light path of the
excited light output from the first light-guiding assembly; and the
second light-guiding assembly is configured to guide one or both of
the first supplementary light and at least part of the excited
light to exit through a same light emission channel.
2. The light source system according to claim 1, wherein the first
light-guiding assembly comprises a light-splitting component and a
light-reflecting component, the light-splitting component is
configured to transmit/reflect the excitation light and
reflect/transmit at least part of the excited light, and the
light-reflecting component is configured to guide the at least part
of the excited light to the second light-guiding assembly.
3. The light source system according to claim 1, wherein the second
light-guiding assembly comprises a selective optical component, the
selective optical component is configured to reflect/transmit the
first supplementary light or reflect/transmit the first
supplementary light and transmit/reflect at least part of the
excited light.
4. The light source system according to claim 3, wherein the
selective optical component is a light-filtering plate configured
to reflect the first supplementary light and transmit at least part
of the excited light, or the selective optical component is a
reflecting/polarizing plate that is at least partially coated with
film and configured to reflect the first supplementary light rather
than the at least part of the excited light, or the selective
optical component is a light-filtering plate that is partially
coated with film or provided with a polarizing plate.
5. The light source system according to claim 3, wherein the second
light-guiding assembly further comprises a scattering component
or/and a light-homogenizing component disposed between the first
supplementary light source and the selective optical component.
6. The light source system according to claim 3, wherein the second
light-guiding assembly further comprises a second condensing lens,
the second condensing lens being configured to converge the first
supplementary light output from the scattering component or/and the
light-homogenizing component to the selective optical component,
and a converging focus of the first supplementary light being on
the selective optical component.
7. The light source system according to claim 1, wherein the light
source system further comprises a light-filtering apparatus, the
light-filtering apparatus being located between the first
light-guiding assembly and the second light-guiding assembly, or
located in the same light emission channel.
8. The light source system according to claim 7, wherein the
wavelength conversion apparatus is a reflective color wheel, the
light-filtering apparatus is a light-filtering wheel, and the
light-filtering wheels is disposed on an outer circumference or an
inner circumference of the reflective color wheel and forms an
integral structure with the reflective color wheel.
9. The light source system according to claim 8, wherein the second
light-guiding assembly is located between the first light-guiding
assembly and the light-filtering wheel, or located at downstream of
the light path of the excited light output from the light-filtering
wheel.
10. The light source system according to claim 7, wherein the
wavelength conversion apparatus is a transmissive color wheel, the
light-filtering apparatus is a light-filtering wheel, the
light-filtering wheel being disposed separately from the
transmissive color wheel, and at least some components of the
second light-guiding assembly are located in a gap between the
light-filtering wheel and the transmissive color wheel.
11. The light source system according to claim 10, wherein
respective rotation axes of the light-filtering wheel and the
transmissive color wheel are parallel or coincident to each
other.
12. The light source system according to claim 7, wherein the light
source system further comprises a light-homogenizing apparatus
located in the same light emission channel.
13. The light source system according to claim 1, wherein the light
source system further comprises a light-filtering apparatus and a
light-homogenizing apparatus, the light-filtering apparatus being
located between two components of the first light-guiding assembly,
the light-homogenizing apparatus being located in the light
emission channel of the excited light output from the
light-filtering apparatus, and the first supplementary light source
and the second light-guiding assembly being located in a light
emission channel of the excited light output from the
light-homogenizing apparatus.
14. The light source system according to claim 1, wherein the first
supplementary light is one or more of red light, green light or
blue light.
15. The light source system according to claim 3, wherein two first
supplementary light sources are provided, and the two first
supplementary light sources respectively emit red light and green
light as the first supplementary light, the second light-guiding
assembly further comprises a light-splitting component, the red
light and the green light irradiate onto the selective optical
component through the light-splitting component.
16. A projection device, comprising a light source system wherein
the light source system comprises: an excitation light source, a
first supplementary light source, a first light-guiding assembly, a
wavelength conversion apparatus, and a second light-guiding
assembly, wherein: the excitation light source is configured to
emit excitation light the first supplementary light source is
configured to emit first supplementary light the first
light-guiding assembly is configured to guide the excitation light
to the wavelength conversion apparatus; the wavelength conversion
apparatus is configured to convert the excitation light to excited
light and emit the excited light to the first light-guiding
assembly; the first light-guiding assembly is further configured to
guide the excited light, so that the excited light irradiate onto
the second light-guiding assembly; at least some components of the
second light-guiding assembly are disposed in a light path of the
excited light output from the first light-guiding assembly; and the
second light-guiding assembly is configured to guide one or both of
the first supplementary light and at least part of the excited
light to exit through a same light emission channel.
17. The projection device according to claim 16, wherein the first
light-guiding assembly comprises a light-splitting component and a
light-reflecting component, the light-splitting component is
configured to transmit/reflect the excitation light and
reflect/transmit at least part of the excited light, and the
light-reflecting component is configured to guide the at least part
of the excited light to the second light-guiding assembly.
18. The projection device according to claim 16, wherein the second
light-guiding assembly comprises a selective optical component, the
selective optical component is configured to reflect/transmit the
first supplementary light or reflect/transmit the first
supplementary light and transmit/reflect at least part of the
excited light.
19. The projection device according to claim 18, wherein the
selective optical component is a light-filtering plate configured
to reflect the first supplementary light and transmit at least part
of the excited light, or the selective optical component is a
reflecting/polarizing plate that is at least partially coated with
film and configured to reflect the first supplementary light rather
than the at least part of the excited light, or the selective
optical component is a light-filtering plate that is partially
coated with film or provided with a polarizing plate.
20. The projection device according to claim 16, wherein the light
source system further comprises a light-filtering apparatus, the
light-filtering apparatus being located between the first
light-guiding assembly and the second light-guiding assembly, or
located in the same light emission channel.
Description
TECHNICAL FIELD
[0001] The present invention relates to the field of optical
technologies, and more particularly to a light source system and a
projection device.
BACKGROUND
[0002] At present, solid-state light sources have been widely used
in general illumination, special illumination and projection
display due to their characteristics of long service life and
environmental protection etc. Thereamong, white light solid-state
light sources have great development potential in the field of
illumination.
[0003] The prior art provides a white light source that uses
excited light to excite fluorescent powder in order to achieve
ultra-high brightness. The white light source excites yellow
fluorescent powder of YAG:Ce material by adopting a blue-violet
laser with a wavelength in a range of 440 nm to 455 nm to generate
yellow fluorescence with high-efficiency, and forms blue laser
light by adopting a blue laser with a wavelength in a range of 440
nm to 470 nm to complement the yellow fluorescence, by which the
yellow fluorescence and the blue laser light are combined to form a
white light source.
[0004] This type of white light source can be used in the field of
projection display where a high brightness light source is
required, for example, in single-piece, two-piece, three-piece DLP,
LCD or LCOS projectors. The white light emitted by the white light
source is divided in spectrum into three primary colors of red
light, green light and blue light, which are respectively incident
on one or more light modulation components, such as DMD, LCD chip
or LCOS chip. The three primary colors of red, green and blue light
modulated by the light modulation components are combined in
spectrum and output to a screen through a projection lens so as to
form a color image.
[0005] Due to the high efficiency of the blue-violet laser, thermal
stability and long-term reliability thereof are good. The
fluorescent powder of YAG:Ce material has high luminescence quantum
efficiency and good thermal stability, so the combination of the
blue-violet laser and the YAG:Ce fluorescent powder forms a white
light source with high efficiency, high reliability, and high
brightness. That is, as for two-piece and three-piece projectors, a
white light source is generally realized by combining a blue-violet
laser and yellow fluorescent powder.
SUMMARY
Technical Problem
[0006] However, in a white light source in which a blue-violet
laser is used to excite fluorescent powder of YAG:Ce material to
form white light, since the spectral intensity of the yellow light
emitted by the fluorescent powder of YAG:Ce material which is
excited is weak in the red segment, the white light source has a
white balance problem, that is, the white light balance point
deviates from the Planck blackbody curve, and presents a greenish
white color.
[0007] In order to avoid the white balance problem of the two-piece
and three-piece projectors, the prior art provides a method in
which the excessive green light component in the combined white
light is filtered out, so that the white balance point restores to
the Planck blackbody curve so as to solve the white balance
problem. However, since the green light component is filtered out
in this method, light emitting efficiency of the white light source
is reduced.
[0008] In order to solve the white balance problem of the white
light source, the prior art provides another method in which a red
laser is added to the yellow fluorescence or red fluorescence, for
example, a laser with a spectral range of around 638 nm or 650 nm
is added to the yellow fluorescence to increase the red light
component in the combined light in order to solve the white balance
problem.
[0009] As shown in FIG. 1, the prior art provides a structure of a
light source system in which a red laser is added to the yellow
fluorescence. The light source system includes a blue excitation
light source 11, a red supplementary light source 12, a
light-splitting-and-filtering plate 13 having a center region and
an edge region, a color wheel 14, a condensing lens 15, and a
light-homogenizing apparatus 16. The center region of the
light-splitting-and-filtering plate 13 transmits blue light and red
light and reflects green light, while the edge region reflects red,
green, and blue light. Thus, the blue excitation light emitted by
the blue excitation light source 11 and the red light emitted by
the red supplementary light source 12 are transmitted to the color
wheel 14 through the center region of the
light-splitting-and-filtering plate 13. The yellow fluorescent
powder on the color wheel 14 absorbs the blue excitation light
while scattering the red light, and emits yellow fluorescence and
the scattered red light. The yellow fluorescence and the scattered
red light are incident on the light-splitting-and-filtering plate
13 through the condensing lens 15. The green light in the yellow
fluorescence incident on the center region of the
light-splitting-and-filtering plate 13 is reflected to the
light-homogenizing apparatus 16. The yellow fluorescence and the
red light incident on the edge region of the
light-splitting-and-filtering plate 13 are also reflected to the
light-homogenizing apparatus 16, while there is loss in the red
light in the yellow fluorescence incident on the center region of
the light-splitting-and-filtering plate 13 and the scattered red
light when being transmitted.
[0010] In the existing white light source mentioned above, the red
light emitted from the red supplementary light source is lost by
about 5% to 10% caused by being scattered by the fluorescent
material, and is lost by about 10% due to being collected by the
condensing lens after forming Lambertian light distribution, and
then part of the light is lost due to being transmitted by the
center region of the light-splitting-and-filtering plate, and this
lost part of light is approximately 10%. Therefore, loss of the red
light emitted by the red complementary light source is relatively
large, and the light utilization rate of the red light is
relatively low, which is about 60-70%. While the red complementary
light source is of high cost, has higher requirements for heat
dissipation, and requires severe heat dissipation conditions, thus,
the low utilization rate of the red light will lead to substantial
increase in cost, which is disadvantageous. Likewise, in order to
get better green light, a method of adding a green laser to the
light source is also adopted, which is similar to the above method
of adding a red laser and has the problem of low utilization rate
either.
[0011] For a single-piece projector, the blue-violet laser is
adopted to excite blue, green, and red segment sequence to generate
sequence of red, green, and blue light to form white light. The
blue light is provided by the blue-violet laser itself. The green
light is generated by the blue-violet laser exciting the green
fluorescent powder. The red light is generated by the blue-violet
laser exciting the red fluorescent powder, while the red
fluorescent powder have serious efficiency degradation problems
when in a higher energy density, resulting in an excessively low
red light ratio and affecting white balance and image quality.
[0012] In order to avoid the white balance problem of the
single-piece projectors, a method of increasing the red color
segment is generally used to maintain the white balance in the
prior art, however, this will reduce the brightness of the white
light and the overall light effect.
[0013] Therefore, in view of the deficiencies of the prior art, it
is urgent to propose a technical solution capable of improving the
utilization rate of complementary light sources such as red and
green light.
Technical Solutions
[0014] In view of this, the present invention provides a light
source system and a projection device to solve the problem of low
light utilization rate of red light or light of other color emitted
by a complementary light source including a red supplementary light
source in the prior art.
[0015] In order to achieve the above object, the present invention
provides the following technical solution: a light source system
including an excitation light source, a first supplementary light
source, a first light-guiding assembly, a wavelength conversion
apparatus, and a second light-guiding assembly. The excitation
light source is configured to emit excitation light. The first
supplementary light source is configured to emit first
supplementary light. The first light-guiding assembly is configured
to guide the excitation light to the wavelength conversion
apparatus. The wavelength conversion apparatus is configured to
convert the excitation light to excited light and emit the excited
light to the first light-guiding assembly. The first light-guiding
assembly is further configured to guide the excited light, so that
the excited light irradiate onto the second light-guiding assembly.
At least some components of the second light-guiding assembly are
disposed in a light path of the excited light output from the first
light-guiding assembly. The second light-guiding assembly is
configured to guide one or both of the first supplementary light
and at least part of the excited light to exit through a same light
emission channel.
[0016] Further, the first light-guiding assembly comprises a
light-splitting component and a light-reflecting component, the
light-splitting component is configured to transmit/reflect the
excitation light and reflect/transmit at least part of the excited
light, and the light-reflecting component is configured to guide
the at least part of the excited light to the second light-guiding
assembly.
[0017] Further, the second light-guiding assembly includes a
selective optical component, the selective optical component is
configured to reflect/transmit the first supplementary light or
reflect/transmit the first supplementary light and transmit/reflect
at least part of the excited light.
[0018] Still further, the selective optical component is a
light-filtering plate configured to reflect the first supplementary
light and transmit at least part of the excited light, or the
selective optical component is a reflecting/polarizing plate that
is at least partially coated and configured to reflect the first
supplementary light and not to transmit the at least part of the
excited light, or the selective optical component is a
light-filtering plate that is partially coated or provided with a
polarizing plate.
[0019] Still further, the second light-guiding assembly further
includes a scattering component or/and a light-homogenizing
component disposed between the first supplementary light source and
the selective optical component.
[0020] Still further, the second light-guiding assembly further
includes a second condensing lens, the second condensing lens being
configured to converge the first supplementary light output from
the scattering component or/and the light-homogenizing component to
the selective optical component, and a converging focus of the
first supplementary light being on the selective optical
component.
[0021] Further, the light source system further includes a
light-filtering apparatus, the light-filtering apparatus being
located between the first light-guiding assembly and the second
light-guiding assembly, or located in the same light emission
channel.
[0022] Still further, the wavelength conversion apparatus is a
reflective color wheel, the light-filtering apparatus is a
light-filtering wheel, and the light-filtering wheels is disposed
on an outer circumference or an inner circumference of the
reflective color wheel and forms an integral structure with the
reflective color wheel.
[0023] Still further, the second light-guiding assembly is located
between the first light-guiding assembly and the light-filtering
wheel, or located at downstream of the light path of the excited
light output from the light-filtering wheel.
[0024] Still further, the wavelength conversion apparatus is a
transmissive color wheel, the light-filtering apparatus is a
light-filtering wheel, the light-filtering wheel being disposed
separately from the transmissive color wheel, and at least some
components of the second light-guiding assembly are located in a
gap between the light-filtering wheel and the transmissive color
wheel.
[0025] Still further, respective rotation axes of the
light-filtering wheel and the transmissive color wheel are parallel
or coincident to each other.
[0026] Still further, the light source system further includes a
light-homogenizing apparatus located in the same light emission
channel.
[0027] Further, the light source system further includes a
light-filtering apparatus and a light-homogenizing apparatus, the
light-filtering apparatus being located between two components of
the first light-guiding assembly, the light-homogenizing apparatus
being located in the light emission channel of the excited light
output from the light-filtering apparatus, and the first
supplementary light source and the second light-guiding assembly
being located in a light emission channel of the excited light
output from the light-homogenizing apparatus.
[0028] Further, the excitation light is blue light, violet light or
ultraviolet light.
[0029] Further, the first supplementary light is one or more of red
light, green light or blue light.
[0030] Further, two first supplementary light sources are provided,
and the two first supplementary light sources respectively emit red
light and green light as the first supplementary light, the second
light-guiding assembly further includes a light-splitting
component, the red light and the green light irradiate onto the
selective optical component through the light-splitting
component.
[0031] Further, the wavelength conversion apparatus includes a
wavelength conversion material, and the wavelength conversion
material is a yellow fluorescent powder.
[0032] Further, an etendue of the first supplementary light is
smaller than an etendue of the excited light.
[0033] To achieve the other object above, the present invention
provides a projection device including the light source system
described above.
Beneficial Effect
[0034] Compared with the prior art, the technical solution provided
by the present invention has the following advantages:
[0035] In the present invention, ratio of the first supplementary
light in the combined light can be increased by supplementing the
excited light with the first supplementary light, and meanwhile, at
least part of the excited light is directly output from the same
emission channel through the second optical guiding assembly, and
the first supplementary light is not scattered by the wavelength
conversion apparatus, thereby avoiding light loss of the first
supplementary light due to being scattered by the wavelength
conversion apparatus, which greatly improves the light utilization
rate of the first supplementary light.
BRIEF DESCRIPTION OF DRAWINGS
[0036] In order to more clearly illustrate the embodiments of the
present invention or the technical solutions in the prior art, the
drawings used in the embodiments or the description of the prior
art will be briefly described below. Obviously, the drawings in the
following description are only some embodiments of the present
invention, and for those skilled in the art, other drawings can be
obtained according to these drawings without any creative work.
[0037] FIG. 1 is a schematic structural view of a light source
system provided by the prior art;
[0038] FIG. 2 is a schematic structural diagram of a light source
system according to a first embodiment of the present
invention;
[0039] FIG. 3 is a schematic structural diagram of a light source
system according to a second embodiment of the present
invention;
[0040] FIG. 4 is a schematic diagram showing a corresponding
relationship between reflectance of coating of a selective optical
component and spectra of a first complementary light and excited
light in the embodiment shown in FIG. 3;
[0041] FIG. 5 is a schematic diagram showing a corresponding
relationship between transmittance of coating of a selective
optical component and spectra of a first complementary light and
excited light in another implementation of the second embodiment of
the present invention;
[0042] FIG. 6 is a schematic structural diagram of a light source
system according to a third embodiment of the present
invention;
[0043] FIG. 7 is a schematic diagram showing a corresponding
relationship between transmittance of coating of a selective
optical component and spectra of a first complementary light and
excited light in another implementation of the third embodiment of
the present invention;
[0044] FIG. 8 is a schematic structural diagram of a light source
system according to a fourth embodiment of the present
invention;
[0045] FIG. 9 is a schematic structural diagram of a light source
system according to a fifth embodiment of the present
invention;
[0046] FIG. 10 is a schematic structural diagram of a light source
system according to a sixth embodiment of the present invention;
and
[0047] FIG. 11 is a schematic structural diagram of a light source
system according to a seventh embodiment of the present
invention.
DESCRIPTION OF EMBODIMENTS
[0048] The present invention provides a light source system, and
the light source system includes at least two light sources, a
wavelength conversion apparatus, a first light-guiding assembly and
a second light-guiding assembly. The at least two light sources
include an excitation light source and a first supplementary light
source. The excitation light source is used for emitting excitation
light; the first supplementary light source emits a first
supplementary light. The first light-guiding assembly is used for
guiding the excitation light emitted by the excitation light source
to the wavelength conversion apparatus. The wavelength conversion
apparatus can convert the excitation light to excited light and
emit the excited light to the first light-guiding assembly. The
first light-guiding assembly is also used for guiding excited
light, causing the excited light to be incident on the second
light-guiding assembly. Preferably, an etendue of the first
supplementary light is smaller than an etendue of the excited
light. The second light-guiding assembly is used for guiding one or
both of at least part of the excited light and the first
supplementary light, such that the first supplementary light and at
least part of the excited light are output from the same light
emission channel.
[0049] Preferably, the structural dimension of the selective
optical component included in the second light-guiding assembly may
be set based on one or a combination of the amount of light loss
when the excitation light passes through the selective optical
component, the amount of light loss when the first supplementary
light passes through the selective optical component, and the
amount of light loss when the excited light passes through the
selective optical component.
[0050] The present invention also provides a projection device
including the light source system as described above.
[0051] The light source system provided by the present invention
includes at least two light sources, and the at least two light
sources includes an excitation light source and a first
supplementary light source. The excitation light emitted by the
excitation light source is guided to the wavelength conversion
apparatus by the first light-guiding assembly, and the excitation
light is converted into excited light by the wavelength conversion
apparatus. The excited light is guided by the first light-guiding
assembly to the second light-guiding assembly. The etendue emitted
by the first supplementary light source is less than the etendue of
the excited light. The first supplementary light is combined with
at least part of the excited light by the second light-guiding
assembly and further guided to the same light emission channel and
output therefrom. In this way, by supplementing the first
supplementary light in the excited light, the ratio of the first
supplementary light in the combined light can be increased. At the
same time, since a light-homogenizing apparatus or a
light-homogenizing apparatus and a light-filtering apparatus can be
disposed on the same light emission channel, the second
light-guiding assembly can directly guide the first supplementary
light to the light-homogenizing apparatus or guide the first
supplementary light through the light-filtering apparatus to the
light-homogenizing apparatus without being scattered by the
wavelength conversion apparatus, so that the light loss of the
first supplementary light caused by being scattered by the
wavelength conversion apparatus is avoided, greatly improving the
light utilization rate of the first supplementary light which is,
for example, red light, and probably the light utilization rate of
red light can be increased up to more than 80%.
[0052] The above is the core conception of the present invention.
In order to make the objects, features and advantages of the
present invention more apparent, specific embodiments of the
present invention will be described in detail in connection with
the accompany drawings.
[0053] In the following description, numerous specific details are
set forth in order to provide a full understanding of the present
invention, but the present invention may be implemented in other
ways than those described herein, and those skilled in the art can
make similar applications without departing from the scope of the
present invention. The present invention is not limited by the
specific embodiments disclosed below.
[0054] Secondly, the present invention will be described in detail
in conjunction with the schematic diagrams. When the embodiments of
the present invention are described in detail, for the convenience
of description, the cross-sectional view of the structure of the
apparatus may not be partially enlarged according to the general
ratio, and the schematic diagram is only an example, which should
not limit the protection scope of the present invention. In
addition, three-dimensional dimensions of length, width and depth
should be included in the actual production.
[0055] The present invention will be described in detail with
several embodiments.
Embodiment One
[0056] The present embodiment provides a light source system 20. As
shown in FIG. 2, the light source system 20 includes two light
sources respectively being an excitation light source 21 and a
first supplementary light source 22, and also includes a first
light-guiding assembly 23, a wavelength conversion apparatus 24,
and a second light-guiding assembly 25. In the present embodiment,
as an example, the wavelength conversion apparatus is a reflective
color wheel 24 (such as a wavelength conversion layer directly
coated on a reflective substrate). Of course, the wavelength
conversion apparatus may also be a transmissive wavelength
conversion apparatus (such as a transparent plate and a wavelength
conversion material doped in the transparent plate). Wavelength
conversion materials include, but are not limited to, fluorescent
powder, quantum dot materials, and the like. The wavelength
conversion layer is a wavelength conversion material layer or a
plate obtained by sintering a wavelength conversion material and an
adhesive. Preferably, the wavelength conversion material may be a
yellow fluorescent powder, a yellow-green fluorescent powder, a
green fluorescent powder or the like. As a specific embodiment, the
first light-guiding assembly 23 includes a light-splitting
component which is, for example, an all-reflective plate 231 which
is partially coated, and a light reflecting component which is, for
example, a reflecting mirror 232, while the light-splitting
component and the light reflecting component are oppositely
disposed. As a specific arrangement of the all-reflective plate 231
and the reflecting mirror 232, the all-reflective plate 231 and the
reflecting mirror 232 are both disposed at an angle of 45.degree.
with respect to the horizontal plane but with different
orientations. The all-reflective plate 231 is partially coated at a
region corresponding to the incidence of the excitation light so as
to transmit the excitation light and to reflect the excited light,
while other regions are all set to reflect the excited light, the
excitation light, or both. Further, in order to improve the light
purity of the excited light or the excited light and the first
supplementary light (described further below), an annular
light-filtering wheel may be disposed at an outer circumference or
an inner circumference of the circular color wheel. In other words,
the reflective color wheel and the light-filtering wheel form an
integral structure. In the present invention, the structure in
which the annular light-filtering wheel is disposed on the outer
circumference of the circular color wheel is taken as the example
of the integral structure of the reflective color wheel and the
light-filtering wheel. The type and partitions of the wavelength
conversion material on the reflective or transmissive color wheel,
and the type and partition of the light-filtering plate of the
corresponding integral or partitioned light-filtering wheel
(described further below) may be determined according to the actual
situation, while the partitions of the color wheel and the
light-filtering wheel have their respective rotation angles
matched. In order to improve the utilization rate of the excitation
light and the excited light, the first light-guiding assembly 23
may also include first condensing lenses 233 disposed each between
the all-reflective plate 231 and the reflective color wheel 24,
between the all-reflective plate 231 and the reflecting mirror 232,
between the reflecting mirror 232 and the light-filtering wheel 26,
and between the light-filtering wheel 26 and the second
light-guiding assembly 25. The first condensing lens 233 may be a
convex lens, a concave lens, or a combination of the two, or the
like, and moreover, number of the first condensing lenses 233 can
be determined according to actual needs.
[0057] The excitation light source 21 and the first supplementary
light source 22 described above are used to emit the excitation
light and the first supplementary light, respectively. The
excitation light source 21 and the first supplementary light source
22 each include a solid state light emitting assembly, and the
solid state light emitting assembly is a single solid state light
emitting component or an array of solid state light emitting
components including a plurality of solid state light emitting
components. The solid state light emitting component may be a laser
diode (LD) or a light emitting diode (LED) or the like. The
excitation light is blue light, violet light, or ultraviolet light
or the like. The spectral range of the first supplementary light is
different from the spectral range of the excitation light, and the
spectral range of the first complementary light is narrower than
the spectral range of the excited light, thereby increasing the
color saturation of the combined light of the excited light and the
first complementary light. Preferably, the etendue of the first
supplementary light is smaller than the etendue of the excited
light. For example, the color of the first supplementary light
emitted by the first supplementary light source 22 can be set
according to different requirements for the excited light. For
example, when light of a certain color is missing or insufficient
in the excited light, the first supplementary light is light of
that color. For example, the first supplementary light may be one
or more of red light, green light, blue light, or the like.
Preferably, the color of the first supplementary light is
consistent with a certain color of the light that is missing or
insufficient in the excited light, and the first supplementary
light is, for example, a laser light emitted by a solid state light
source while the excited light is fluorescence generated, for
example, by the wavelength conversion material being excited.
Because there is overlapping between the spectra of the excited
light and the fluorescence, it is possible to obtain better image
quality and higher light-supplementing efficiency by performing
light-combination by etendue of the excited light and the
fluorescence.
[0058] The second light-guiding assembly 25 includes a selective
optical component 251. In addition, in order to obtain a better
light-emitting effect of the first supplementary light, the second
light-guiding assembly 25 further includes a scattering plate 252
which is disposed between the first supplementary light source 22
and the optional optical component 251 and may serve as a
scattering component, and a fly-eye lens pair 253 which can be used
as a light-homogenizing component. The scattering plate 252 can
perform decoherence processing to the first supplementary light
output by the solid state light emitting assembly included in the
first supplementary light source 22. The scattering plate 252 may
be a rotating scattering plate, a vibrating scattering plate, or
the like. Since decoherence processing to the first supplementary
light output by the solid state light emitting assembly is
performed by the scattering plate 252, the speckle phenomenon in
the combined light of the excited light and the first complementary
light is avoided. In addition, preferably, a second condensing lens
254 is disposed between the fly-eye lens pair and the selective
optical component 251, so that the first complementary light can be
converged at the selective optical component 251 after being
homogenized by the fly-eye lens pair. Preferably, the mutual
position of the second condensing lens 254 and the selective
optical component 251 is configured such that the converging focus
of the first complementary light is positioned on the selective
optical component 251. Since the converging focus of the first
supplementary light is on the selective optical component 251 and
the selective optical component 251 reflects the first
supplementary light to the light emission channel, an area of a
region, which is used for reflecting the first supplementary light,
on the selective optical component 251 is reduced. Correspondingly,
it is possible to reduce the light loss of the excited light whose
spectral range is close to that of the first supplementary light
and the excited light containing a portion of light within the
spectral range when the excited light passing through said region
and being reflected, thereby improving the light utilization rate.
In addition, the first light-guiding assembly may further include a
square bar (not shown) that can function as a light-homogenizing
apparatus, and the square bar is disposed between the first
condensing lens 233 and the light-filtering wheel 26 between the
light-filtering wheel 26 and the second light-guiding assembly
25.
[0059] The following is a detailed description of the selective
optical component. It can be understood that any of the selective
optical components described below can be applied not only to the
present embodiment but also to other embodiments unless otherwise
stated. The selective optical component reflects the first
supplementary light or reflects the first supplementary light and
transmits at least part of the excited light. In an implementation,
the selective optical component is a light-filtering plate
including a center film and an edge film, wherein the center film
is smaller in dimension than the edge film. The center film and the
edge film may be an integral film or separate films. The dimension
of the center film may be set according to one or a combination of
the light loss amount of the first supplementary light when passing
through the center film, the light loss amount of the excitation
light when passing through the center film, or the light loss
amount of the excited light passing through the center film. In
another implementation, the selective optical component is an
individual reflecting plate or polarizing plate, or the selective
optical component includes a reflecting plate or a polarizing plate
and a fixing member for fixing the reflecting plate or the
polarizing plate (not shown in drawing). A coating is disposed on
the reflecting plate or the polarizing plate such that the
reflecting plate or the polarizing plate reflects the first
complementary light and at least part of the excited light is
transmitted from the reflecting plate without being reflected.
Preferably, the first complementary light is incident on one of
reflecting plate and the polarizing plate and forms a spot, while
the dimension of the reflecting plate and the polarizing plate
matches this spot, that is, the entire area of the reflecting plate
or the polarizing plate is coated, so that it is possible to reduce
the adverse effect of the reflecting plate or the polarizing plate
on the reflection of the excited light. In addition, it is possible
that the reflecting plate does not include a coating, and in the
excited light, portion of excited light incident on the reflecting
plate is totally reflected without being transmitted, resulting in
that this portion of excited light is subject to a relatively large
light loss, but the cost can be reduced with respect to the case in
which a coating is disposed on the reflecting plate. In still
another implementation, the selective optical component is a
light-filtering plate, and the light-filtering plate is provided
with a first coating or a polarizing plate at the center region.
For the case where a coating is provided at the center region of
the light-filtering plate, one side of the coating region of the
light-filtering plate reflects the first supplementary light, while
the other side transmits the excited light or transmits part of the
excited light but reflects the light, of which the spectral range
is close to that of the first complementary color, in the excited
light, causing a certain loss. In the case where a polarizing plate
is provided at the center region of the light-filtering plate, the
edge region of the light-filtering plate transmits the excited
light, and the polarizing plate is a polarizing plate for the first
complementary light, that is, this polarizing plate reflects the
first supplementary light having the first polarization state and
transmits the second supplementary light having the second
polarization state. However, it can be seen that, in general, for
the first supplementary light source 22 including the solid state
light emitting assembly, the first supplementary light emitted by
the first complementary light source 22 can be controlled to be a
light having substantially one polarization state, such as a P
state. Therefore, the polarizing plate reflects the first
complementary light having the P-polarization state, and at the
same time, transmits partial excited light, which has an
S-polarization state, in the excited light. However, for example,
the fluorescence which can serve as excited light includes light
having two polarization states of both the P state and the S state,
and thus, by providing a polarizing plate in the light-filtering
plate at the region corresponding to the incidence of the first
complementary light, the light, of which the polarization state is
different from that of the first complementary light, in the
excited light and the first complementary light can be guided to
emit from the same light emission channel. Therefore, only light of
P-polarization state of the light that passes through the
polarizing plate region in the excited light is reflected and lost,
which decrease loss of the excited light when passing through the
polarizing plate, and the utilization efficiency of the excited
light is higher. In another implementation, the selective optical
component is a wavelength light-filtering plate with a second
coating provided at the center region. The second coating has
different light-filtering curves for light of different
polarization states. For example, in the case where the first
complementary light is red light of P-polarization state and the
excited light includes green, blue and red light having two
polarization states respectively, the second coating can reflect
the first complementary light which is red light of polarization
state P, and transmits green light of P and S-polarization states
in the excited light, blue light of P and S-polarization states,
and red light of S-polarization state, while only the red light
with P-polarization state will be reflected by the second coating
and lost. Therefore, when comparing with the case where a
polarizing plate is provided at the center region of the
light-filtering plate and only allows light of one of the two
polarization states included in each light to be transmitted, the
second coating may allow light of two polarization states included
in part of each light to be transmitted, which further reduces the
loss of the excited light passing through the second coating.
Preferably, in the above various embodiments, the center film of
each light-filtering plate, the first coating provided at the
center region, an area of the polarizing plate at the center
region, or an area of the second coating provided at the center
region of the wavelength light-filtering plate are smaller than 50%
of the useful spot area. The useful spot area refers to the area of
the spot formed on the entire light-filtering plate by the excited
light output from the wavelength conversion apparatus. In addition,
it can be understood that the above description of the positions of
the center and the center region are not essential, which can be
adjusted according to actual needs. It should also be noted that
the above describes a case where the selective optical component
reflects the first supplementary light or reflects the first
supplementary light and transmits at least part of the excited
light, however, according to the needs of light path design,
optical component layout and so on, it is also possible to make
appropriate adjustment by referring to any of the above selective
optical components, so that the selective optical component
transmits the first supplementary light or transmits the first
supplementary light and reflects at least part of the excited
light.
[0060] The light source system provided by the embodiment of the
present invention will be described below in a specific example
with reference to FIG. 2. It is assumed that the excitation light
emitted by the excitation light source 21 is the blue excitation
light B, and the first complementary light emitted by the first
supplementary light source 22 is the red light R. In addition, it
may be implemented that the first supplementary light may also be
green light, or the first supplementary light may include red light
and green light. The wavelength conversion apparatus is a
reflective wavelength conversion apparatus, and the wavelength
conversion material is yellow fluorescent powder. The light path
principle of the light source system 20 is as follows. The blue
excitation light B sequentially passes through the all-reflective
plate 231 with a coating provided at a region and the first
condensing lens 233 so as to be incident on the color wheel 24, and
the yellow excited light Y generated by the yellow fluorescent
powder of the excitation color wheel 24 or the yellow excited light
Y and the unconverted blue excitation light B are reflected to the
first condensing lens 233. Then the yellow excited light Y is
reflected by the all-reflective plate 231, and the unconverted blue
excitation light B is reflected by regions of the all-reflective
plate except for the area other than the coating region where the
excitation light is incident. After that, the yellow excited light
Y or the yellow excited light Y and the unconverted blue excitation
light B are guided to the first condensing lens 233 and the
reflecting mirror 232 to be incident on the light-filtering wheel
26, and then pass through the light-filtering wheel 26 so as to be
incident on the light-filtering plate 251 which serves as a
selective optical component and is provided with a polarizing plate
251A at the center region. The light, of which the polarization
state is different from that of the first complementary light, in
the yellow excited light Y irradiate onto the polarizing plate 251A
is transmitted and the light of which the polarization state is the
same as that of the first complementary light is reflected by the
polarizing plate 251A, which results in loss. Therefore, the light,
which is reflected by the polarizing plate and has a polarization
state that is different from that of the first complementary light,
in the excited light is reduced, thereby improving the utilization
rate of the excited light. The yellow excited light Y irradiate
onto the region other than the polarizing plate 251A of the
light-filtering plate 251 is transmitted. The red light R emitted
by the first supplementary light source 22 is de-coherent processed
by the scattering plate 252 and is homogenized by the fly-eye lens
pair 253, and then is converged at the polarizing plate 251A and is
reflected to the light emission channel. In this way, the excited
light can be supplemented with red light R, and the red light R of
the first complementary light and the red excited light can achieve
light-combination by etendue through the polarizing plate 251A.
Since the red light R is directly guided to the light emission
channel by the polarizing plate 251A without being scattered by the
wavelength conversion apparatus, light loss of the red light R is
reduced and the light utilization rate of the red light R is
improved. It can be seen that the red light R and the yellow
excited light Y can be incident on the light modulation components,
such as a one-piece or three-piece DMD light modulation components,
through the same light emission channel.
[0061] In the present embodiment, the first light-guiding assembly
guides the excitation light emitted by the excitation light source
to the wavelength conversion apparatus and guides the excited light
output from the wavelength conversion apparatus to the
light-filtering apparatus so as to be incident on the second
light-guiding assembly, and moreover, the second light-guiding
assembly guides the first supplementary light emitted by the first
supplementary light source to be combined with the excited light
incident on the second light-guiding assembly in order to irradiate
into the light emission channel. Since the first supplementary
light is not scattered by the wavelength conversion apparatus,
light loss of the first supplementary light is greatly reduced,
thereby improving light-supplement efficiency of the first
supplementary light.
[0062] It should be emphasized that in order to make the
description more concise, description of other embodiments and the
components and structures in the corresponding drawings that are
the same as those of the Embodiment One can be obtained with
reference to the above description and will not be repeated.
Embodiment Two
[0063] The present embodiment provides another light source system
30. As shown in FIG. 3, the main difference between the light
source system 30 and the light source system 20 shown in FIG. 2
lies in the arrangement of the second light-guiding assembly 35.
Specifically, the second light-guiding assembly 35 is different
from that of Embodiment One, wherein the scattering component and
the light-homogenizing component are not disposed between the
selective optical component 351 and the first supplementary light
source 32, and further, a light-homogenizing apparatus 37 is
disposed on the same light emission channel of the first
supplementary light and the excited light. The above-described
light source system 30 provided by the embodiment is described
below with a specific example. It is assumed that the excitation
light emitted from the excitation light source 31 is blue
excitation light B, the first supplementary light emitted by the
first supplementary light source 32 is red light R, the wavelength
conversion apparatus is a reflective color wheel 34, and the
wavelength conversion material is excited by the excitation light
to generate one or more of the excited light of blue B, green G,
and red R, while specific condition of the excited light may be
determined according to the number and type of the light modulation
component. By guidance of the first light-guiding assembly 33, the
excited light is output from the reflective color wheel 34 and
incident on the light-filtering wheel 36. The excited light output
from the light-filtering wheel 36 is further incident on the
selective optical component 351 of the second light-guiding
assembly 35, and irradiate to the fly-eye lens pair 37, which can
be used as a light-homogenizing apparatus, together with the red
light R, which can serve as the first supplementary light.
Moreover, in the present embodiment, the first supplementary light
source 32 adopts an array of red lasers which emits a red laser R,
and the excitation light source 31 adopts an array of blue lasers
which emits a blue laser B. The blue laser B excites the
fluorescent material, which can be used as a wavelength conversion
material, on the reflective color wheel 34 to generate one or more
of the above-mentioned fluorescence. The red laser R and the red
fluorescence adopt a method of light-combination by etendue at the
coating of the selective optical component 351. Referring to FIG.
4, FIG. 4 schematically shows the spectrum RP of the red laser,
spectrum RL of the red fluorescence, and the reflectance curve CR
of the coating of the selective optical component 351. Since the
wavelength range of the spectrum of the red laser is narrow and the
wavelength range of the spectrum of the red fluorescence spectrum
is wide, as for a certain range of the peak wavelengths of the red
laser spectrum RL and the red fluorescence spectrum RP, the
wavelength range corresponding to part of the red fluorescence
spectrum RP1 (shown by the thickened curve in FIG. 4) has an
overlapping portion with both the wavelength range of the
reflectance curve CR and the reflectance curve CR. Therefore, it
can be seen that when the coating is reflecting the red laser, it
will inevitably reflect the red fluorescence having the
corresponding wavelength of the overlapping portion, thereby
causing a certain loss of red fluorescence. However, since the
wavelength range of the red fluorescence spectrum is relatively
wide, by appropriately setting the band pass and band elimination
of the coating, the red fluorescence corresponding to the
wavelength range of part of the red fluorescence spectrum RP2
(shown by the dotted line in FIG. 4) located on the right side of
the thickened curve RP1 will not be reflected but instead will be
transmitted and output together with the red laser, thereby
improving the utilization rate of the excited light. In addition,
the red laser occupies a small region at the center of the fly-eye
lens pair 37, and the fluorescence of one or more of the above blue
B, green G, and red R occupies the remaining region, finally
imaging onto the light modulation component. Both the red laser and
the fluorescence can form a spot with good uniformity, and the spot
is finally formed into an image by the projection lens and is
observed by the human eye. Therefore, the fly-eye lens is fully
utilized to homogenize the light to form a good surface
distribution, such that the cost is reduced by omitting optical
components such as the scattering component and the
light-homogenizing component, and meanwhile, it is still possible
to ensure that the output light is within an acceptable range.
Further, referring further to FIG. 5, in still another
implementation, as regarding to the selective optical component 351
having a coating with characteristics shown in FIG. 4 mentioned
above, the selective optical component 351 can also be further
modified to improve the polarization state characteristics shown in
FIG. 5. For example, in a feasible modification, the modified
selective optical component can be obtained by providing a coating
on the polarizing plate, and the modified selective optical
component has the reflectance and transmittance characteristics
shown in FIGS. 4 and 5 described above. When the red laser R is
light of S-polarization state light and the excited light is red
fluorescence and includes light having polarization states of both
P-state and S-state, the modified selective optical component
reflects the red light R of S-polarization state, and moreover, in
addition to the loss caused by reflecting light of S-polarization
state in the red fluorescence of which the wavelength range is
substantially the same as the wavelength corresponding to the
spectral range of the red laser R, light having polarization states
of both P-state and S-state in the red fluorescence located outside
the substantially same wavelength range described above can be
transmitted through the modified selective optical component 351,
making it possible to significantly reduce the loss of red
fluorescence while ensuring that the red laser R has high
light-supplement efficiency. Therefore, according to the
description above, with the modified selective optical component
351, it is possible to optically realize light-combination by
etendue and polarization state light-combination of the red laser
and the red fluorescence incident thereon.
Embodiment Three
[0064] The present embodiment provides another light source system
40. As shown in FIG. 6, the main difference between the light
source system 40 and the light source system 30 shown in FIG. 3
lies in that a first supplementary light source 42' is added.
Specifically, the first supplementary light source 42 and the first
supplementary light source 42' are disposed on the same side of the
selective optical component 451, and the first supplementary light
source 42' and the first supplementary light source 42 are located
on two sides of the light-splitting element 455 included in the
second light-guiding assembly 45. The light-splitting element 455
splits light by wavelength such that a portion of the light emitted
from the first supplementary light source 42' and the first
supplementary light source 42 is transmitted while the other
portion is reflected and output from the same light path to the
selective optical component 451. Therefore, even if two first
supplementary light sources are provided, it is not necessary to
enlarge the area, which corresponds to the incident region of the
first supplementary light, of the selective optical component 451,
so as to avoid increase of light loss when passing through the
selective optical component 451. In addition, it should be noted
that for two or more first supplementary light sources that emit
two or more different colors of light, these first supplementary
light sources may also respectively emit light through different
second light-guiding assemblies corresponding thereto. For example,
it is assumed that two first supplementary light sources emit two
different colors of light, and with respect to the direction of the
light path along which the excited light passes through the
light-filtering wheel, one first supplementary light source and the
second light-guiding assembly corresponding thereto are disposed in
front of the light-filtering wheel, while the other first
supplementary light source and the second light-guiding assembly
corresponding thereto are disposed behind the light-filtering
wheel. In addition, it should be noted that a solid-state light
source capable of emitting light of two different colors may also
be disposed in a first supplementary light source, and the lights
of two different colors irradiate onto the second light-guiding
assembly in substantially parallel directions. The above-described
light source system 40 provided by the present embodiment is
described below with a specific example. It is assumed that the
excitation light emitted from the excitation light source 41 is
blue laser B, the first supplementary light emitted by the first
supplementary light source 42 is red light R, the first
supplementary light emitted by the first supplementary light source
42' is green light G, the wavelength conversion apparatus is a
reflective color wheel 44, and the wavelength conversion material
is excited by the excitation light to generate a yellow excited
light Y or a yellow excited light Y and an unconverted blue
excitation light (not shown). With the guidance of the first
light-guiding assembly 43, the excited light is output from the
reflective color wheel 44 and is incident on the light-filtering
wheel 46, and the excited light output from the light-filtering
wheel 46 is further incident on the second light-guiding assembly
45 and then irradiate to the fly-eye lens pair 47, which can
function as a light-homogenizing apparatus, together with the red
light R or/and the green light G reflected by the selective optical
component 451. In the present embodiment, since the number of the
first supplementary light sources is two and they respectively emit
red light R and green light G as the first supplementary light, for
example, the red fluorescence and the green fluorescence, which
serve as excited light, can be supplemented with red light R and
green light G respectively according to actual needs, thereby
obtaining better image quality.
[0065] In addition, in still another implementation, the color of
the light emitted from first complementary light source 42' can be
changed into blue from green. That is, the two first supplementary
light sources respectively emit a supplementary blue laser and a
supplementary red laser. The excitation blue laser emitted by the
excitation light source 41 excites the wavelength conversion
material to generate yellow fluorescence. Preferably, the
excitation light source 41 that does not excite the wavelength
conversion material does not operate when the first complementary
light source that emits blue laser is operating. With further
reference to FIG. 7, FIG. 7 schematically shows the spectrum BE of
the excitation blue laser, the spectrum BL of the complementary
blue laser, the spectrum RP of the complementary red laser, the
spectrum YP of the yellow fluorescence, and the transmittance curve
CT of the coating of the selective optical component 451, while the
wavelength range of the blue laser emitted by the first
complementary light source is greater than that of the blue laser
emitted by the first light source 41. Specifically, a blue laser
close to blue-violet is used as the excitation blue laser to excite
the fluorescent powder, and since the excitation efficiency of the
blue laser which is blue-violet is higher than that of the blue
laser of other wavelengths, it is possible to achieve highly
efficient fluorescence excitation and also guarantee the purity of
the color gamut by using a short-wavelength excitation blue laser
to excite the fluorescent powder and adopting a supplementary blue
laser of a slightly longer wavelength as the blue primary light of
the light source system. Moreover, by properly setting the
transmittance curve of the coating, the coating can transmit most
of the yellow fluorescence while transmitting the excitation blue
laser and reflecting the supplementary blue laser and the
supplementary red laser. Therefore, the coating having the
transmittance curve characteristics shown in FIG. 7 can reduce loss
of the excited light while ensuring the light-supplement efficiency
of the supplementary light. In addition, since the yellow
fluorescence Y, which is generated by the excitation blue laser B
emitted from the excitation light source 41 exciting the reflective
color wheel 44, substantially does not include blue light, by
setting a first complementary light source that emits a blue laser,
the color coordinate of the blue light is set to be more conform to
the color gamut requirement. When part or all of the blue light of
the light source system is provided by the blue light emitted by
the first supplementary light source, the color coordinate of the
blue light will be better, and of course, the utilization rate is
also higher. In addition, both the excitation blue laser and the
first supplementary light can be reflected by the selective optical
component 451 and output to the same light emission channel
together with the yellow excited light Y. The supplementary blue
laser emitted by the first supplementary light source is closer to
the subsequent light path. Therefore, the supplementary blue laser
does not need to pass through the first light-guiding assembly so
as to reduce the inevitable light loss caused by the supplementary
blue laser passing through the respective components of the first
light-guiding assembly, and the situation in which the light source
system 40 requires a relatively large amount of blue light can be
satisfied.
Embodiment Four
[0066] The present embodiment provides another light source system
50. As shown in FIG. 8, the main difference between the light
source system 50 and the light source systems shown in FIGS. 2, 3
and 6 lies in positions of the first supplementary light source 52
and the second light-guiding assembly 55, and the components
included in the second light-guiding assembly 55. Specifically,
with respect to the light path along which the excited light is
incident on the light-filtering wheel that can be used as the
light-filtering apparatus, the second light-guiding assembly 55 in
each of the above embodiments is disposed behind the
light-filtering wheel, while the second light-guiding assembly 55
in the present embodiment is disposed in front of the
light-filtering wheel 56. As a specific example of the present
embodiment for providing description of the light source system 50
described above, the case where the excitation light and the
excited light are included is the same as that in Embodiment One,
and will not be repeated here. Referring to FIG. 8, red light R,
which may serve as the first supplementary light, is reflected by
the selective optical component 551 of the second light-guiding
assembly 55 and irradiate onto the light-filtering wheel 56
together with the yellow excited light Y or the yellow excited
light Y and the unconverted blue excitation light B. In the present
embodiment, the selective optical component 551 of the second
light-guiding assembly 55 is disposed between the reflecting mirror
532 and the light-filtering wheel 56. The selective optical
component 551 guides the red light R reflected therethrough and the
yellow excited light Y or the yellow excited light Y and the
unconverted blue excitation light B reflected by the reflecting
mirror 532 to the light-filtering wheel 56. In addition, as an
alternative implementation, the selective optical component 551 of
the second light-guiding assembly 55 may also be disposed between
the all-reflective plate 531 which is partially coated and the
reflecting mirror 532 (not shown), and the selective optical
component 551 guides the red light R reflected therethrough and the
yellow excited light Y or the yellow excited light Y and the
unconverted blue excitation light B reflected by the all-reflective
plate 531 to the reflecting mirror 532 and further to the
light-filtering wheel 56. Further, the excited light and the first
supplementary light are further incident on a third condensing lens
59 and the light-homogenizing apparatus (not shown) after passing
through the light-filtering wheel 56. Preferably, in the present
embodiment, the second light-guiding assembly 55 further includes a
scattering plate 552 and a fourth condensing lens 554 disposed
between the first supplementary light source 52 and the selective
optical component 551. Advantages of providing the scattering plate
552 and the third condensing lens 554 can be referred to the
relevant contents in Embodiment One described above. In the present
embodiment, since the positions at which the first supplementary
light source and the second light-guiding assembly are disposed
utilize the gap between the reflecting mirror 532 and the
light-filtering wheel 56, the structure of the light source system
can be made more compact.
Embodiment Five
[0067] The present embodiment provides another light source system
60. As shown in FIG. 9, the main difference between the light
source system 60 and the light source system 50 shown in FIG. 8
lies in structures of the wavelength conversion apparatus 64 and
the light-filtering apparatus 66, components included in the first
light-guiding assembly 63, and positions of the first supplementary
light source 62 and the second light-guiding assembly 65.
Specifically, the transmissive color wheel 64 which can be used as
the wavelength conversion apparatus and the light-filtering wheel
66 which can be used as the light-filtering apparatus in the
present embodiment have a separate structure, and are respectively
disposed on the light emission light path of the blue excitation
light B emitted by the excitation light source 61 and the excited
light, while at least some components of the second light-guiding
assembly 65 are disposed in the gap between the transmissive color
wheel 64 and the light-filtering wheel 66 which are separated from
each other. The above-described light source system 60 provided by
the embodiment is described below with a specific example. It is
assumed that the excitation light source 61 emits blue excitation
light B, and the first supplementary light emitted by the first
supplementary light source 62 is red light R. The blue excitation
light is firstly incident on the transmissive color wheel 64 via
the first condensing lens 631 included in the first light-guiding
assembly 63 to generate excited light, and the color of the excited
light may be any of the other embodiments described above. After
being transmitted by the transmissive color wheel 64, the excited
light is incident on the selective optical component 651 of the
second light-guiding assembly 65 and irradiate onto the
light-filtering wheel 66 together with the red light R. Preferably,
the first condensing lens 631 included in the first light-guiding
assembly 63 is disposed between the transmissive color wheel 64 and
the selective optical component 651, and further, the excited light
and the red light R that have passed through the light-filtering
wheel 66 are further incident on the fly-eye lens pair 67 which can
serve as a light-homogenizing apparatus. In the present embodiment,
by disposing the selective optical component 651 of the second
light-guiding assembly 65 in the gap between the transmissive color
wheel 64 and the light-filtering wheel 66 that are separated from
each other, the gap is fully utilized. Therefore, it helps to
reduce the overall space occupied by the optical system 60. In
addition, in general, the light-filtering wheel 66 also has the
function of scattering, i.e., decoherence, so when compared with
Embodiment Four, the scattering plate disposed between the first
supplementary light source and the selective optical component can
also be correspondingly reduced in the present embodiment, thereby
saving cost.
Embodiment Six
[0068] The present embodiment provides another light source system
70. As shown in FIG. 10, the main difference between the light
source system 70 and the light source system 50 shown in FIG. 8
lies in positions of the second supplementary light source 72 and
the second light-guiding assembly 75, and components included in
the second light-guiding assembly 75. Therefore, the same
components and light paths as those in FIG. 8 and Embodiment Four
will not be described again. Specifically, with reference to FIG.
10, the second light-guiding assembly 75 of the present embodiment
includes a selective optical component 751, and the selective
optical component 751 transmits the first supplementary light and
reflects the excited light or the excited light and the unconverted
excitation light so as to enable them to irradiate onto the
light-filtering wheel 76 which is disposed outside the color wheel
74 and integrated with the color wheel 74. It can be seen that the
second light-guiding assembly 75 can further include a scattering
plate 752 and a fourth condensing lens 754 disposed between the
first supplementary light source 72 and the selective optical
component 751. The above-described light source system 70 provided
by the present embodiment will be described below with a specific
example. The red light R, which can be used as the first
supplementary light, passes through the all-reflective plate 751
which can be used as the selective optical component and be
partially coated. The center region of the all-reflective plate 751
is provided with a coating that transmits red light R and reflects
yellow excited light Y or yellow excited light Y and unconverted
blue excitation light B, while the edge region of the
all-reflective plate 751 reflects the yellow excited light Y or the
yellow excited light Y and the unconverted blue excitation light B,
so that the all-reflective plate 751 guides the red light R and the
excited light Y, or the red light R, the yellow excited light Y and
the unconverted blue excitation light B to irradiate onto the
light-filtering wheel 76. In addition, similarly, with reference to
the arrangement of the first supplementary light source 72 with
respect to the selective optical component 751, the first
supplementary light source 72 may also be disposed relative to the
all-reflective plate 731 which is partially coated. In this case,
the first supplementary light source 72 is transmitted through the
coating of the all-reflective plate 731, and the excited light or
the excited light and the unconverted excitation light are
reflected by a region other than the coating of the all-reflective
plate 731 in order to be together irradiate to the reflecting
mirror, while this reflecting mirror has the same function as that
of the reflecting mirror described in Embodiment Four. That is, the
all-reflective plate 731 described above may transmit the first
supplementary light and the excitation light and reflect the
excited light or the excited light and the unconverted excitation
light. As described above, in the present embodiment, the
arrangement position of the first supplementary light source is
more flexible, and in addition, with respect to the other
embodiments above, it can be understood that the first
light-guiding assembly and the second light-guiding assembly
actually include the same components, that is, the same components
are shared, which helps to reduce the cost of the light source
system.
Embodiment Seven
[0069] The present embodiment provides another light source system
80. As shown in FIG. 11, since the first supplementary light passes
through the optical assembly, there is inevitably a certain loss of
light. Therefore, in order to further improve the light-supplement
efficiency of the first supplementary light and reduce the number
of optical components through which the first supplementary light
passes, the first supplementary light source 82 and the second
light-guiding assembly 85 in the present embodiment are disposed in
a light emission channel of the excited light output from the
light-homogenizing apparatus 87. The following is a more specific
description of the present embodiment with a specific example, and
the components and light paths which are the same as those in FIG.
3 and Embodiment Two will not be described again. The excited light
output from the light-filtering wheel 86 disposed outside the color
wheel 84 and integrated with the color wheel 84 irradiate to the
fly-eye lens pair 87 which can function as a light-homogenizing
apparatus, and the excited light which has been light-homogenized
and the red light R which can be used as the first supplementary
light are output under the guidance of the selective optical
component of the all-reflective plate 851 which, for example, is
partially coated. Specifically, the red light R can be transmitted
through the coating of the all-reflective plate 851. The excited
light or the excited light and the unconverted excitation light
which has been light-homogenized may be reflected by the region
other than the coating of the all-reflective plate 851, and
moreover, the coated region may reflect part of the excited light
which is incident thereon and of which the wavelength range is
different from the wavelength range corresponding to the spectrum
of the red light R or not only the wavelength range is different
from the wavelength range corresponding to the spectrum of the red
light R but the polarization state thereof is also different, so
that they are output together. The specific structure and function
of the all-reflective plate 851 can be obtained with reference to
the above description, and will not be described in detail. The
co-emission light is incident on the light valve 88 through the
same light emission channel. A reflecting mirror, a condensing
lens, etc. may be disposed in the same light emission channel. The
light valve can be DMD, LCD, LCOS, and the like. In the present
embodiment, with respect to the light path along which the excited
light passes through the first condensing lens 833 and is incident
on the light-homogenizing apparatus 87, the first supplementary
light source 82 and the second light-guiding assembly 85 of the
optical system 80 are both disposed behind the light-homogenizing
apparatus 87, so that the number of optical components through
which the red light R passes can be greatly reduced to reduce light
loss of the red light R accordingly, and the light utilization rate
of the red light R can be increased to about 90% or more. It can be
seen that, in the present embodiment, the first light-guiding
assembly 83 includes a first condensing lens 833 and a
light-homogenizing apparatus 87, that is, the light-filtering wheel
86 is located between two components, i.e. the two first condensing
lenses 833, of the first light-guiding assembly. In addition, in
order to decohere and homogenize the first complementary light, a
scattering plate 852 and a fly-eye lens pair 853 may be disposed
between the first supplementary light source 82 and the
all-reflective plate 851, Therefore, even if the first
supplementary light is not subjected to the homogenization of the
light-homogenizing apparatus 87, a high uniformity can still be
ensured.
[0070] In view of the above various embodiments, it is apparent
that the main object of the present invention is as follows. By
reasonably providing a coating on a selective optical component or
a coating which is applied to the entire selective optical
component, and according to the fact that the etendue of the first
supplementary light is smaller than the etendue of the excited
light, the first supplementary light and the excited light are
light-combined by etendue at the place where the coating is
provided. On the basis of this, according to the fact that the
wavelength spectrum of the first complementary light is smaller
than the wavelength spectrum of the excited light, the first
supplementary light and the excited light are also wavelength
light-combined at the place where the coating is provided. In
addition, it is also possible that the first supplementary light
and the excited light can be light-combined regarding the
polarization state according to the fact that the polarization of
the first complementary light is better (for example, the
polarization state of the excited light can be controlled to be
substantially one type) and the fact that the excited light
includes light of two polarization states (for example, the
polarization states of the fluorescence includes two polarization
states). That is, by reasonably setting the characteristics of the
coating, the first supplementary light and the excited light can be
only light-combined by etendue, and furthermore, they can also be
wavelength light-combined or/and polarization state light-combined
based on the realization of the light-combination by etendue,
thereby improving the light-supplement efficiency of the first
complementary light and reducing the loss of the excited light.
Moreover, co-emission of the first supplementary light and the
excited light described herein include a case where any of the
above-described light combining modes is adopted such that the
first complementary light and part of the excited light are
collectively passing through the coating and output therefrom.
Regarding the reasonable arrangement of the above coating, it can
be obtained by referring to the contents described in Embodiment
Two and FIGS. 4 and 5, and Embodiment Three and FIG. 7 in
combination with the process and method for making a coating in the
prior art. In addition, it can be seen that the reflectance or
transmittance curves of the center film of the light-filtering
plate, the polarizing plate disposed at the center region of the
light-filtering plate, the second coating disposed at the center
region of the wavelength light-filtering plate, the coating of the
separate reflecting plate or the polarizing plate described herein
can be set with reference to the above description, thereby
obtaining the corresponding technical effects. In addition, the
coating described herein is merely a specific example and should
not be construed as limiting the present invention. All optical
components are within the protection scope of the present invention
as long as they can function as the coatings herein and selectively
transmit and reflect different light.
[0071] The present invention also provides a projection device
including a light source system of any of the above
embodiments.
[0072] It should be noted that, according to the actual situation,
the light-homogenizing component and the light-homogenizing
apparatus described above may respectively adopt a
light-homogenizing rod or a fly-eye lens pair. The above
description mainly illustrates an example in which the red light is
taken as the first supplementary light, but it should not be
limited to this, while the first supplementary light may also be
green light, blue light, or the like. In addition, the structure
and position of the light-filtering apparatus can also be set
according to the color of the light passing through the
light-filtering apparatus and the actual needs of the co-emission
light path direction. For example, unlike the case where the
rotating axis of the light-filtering wheel and the rotating axis of
the color wheel are coincident or parallel as described above, the
rotating axis of the light-filtering wheel can also be arranged at
a certain angle of preferably 45.degree. with respect to the
rotating axis of the color wheel. Furthermore, the selective
optical component can selectively transmit or/and reflect at least
part of the excited light depending on the wavelength of the light
incident thereon, the polarization state thereof, or a combination
of the two. Moreover, the combination of the technical means for
reflecting and transmitting the excitation light and the excited
light used in the above light path can be modified according to
actual needs. For example, the X-mirror can be used to replace the
all-reflective plate. At this time, the excitation light can be
reflected by the X-mirror to the color wheel, while the excited
light can also be reflected by the X-mirror to the reflecting
mirror. In addition, a structure in which the transmissive color
wheel and the light-filtering wheel form an integral structure can
be adopted. At this time, the first light-guiding assembly further
includes a reflecting component that is disposed in the light path
of the excited light path and used for reflecting the excited light
to the light-filtering wheel. Furthermore, the co-emission
described above can be understood as that two or more light beams
are output at the same time, and it can also be understood as that
more than one light sequences are output. Description of
co-emission is mainly intended to indicate that the light emission
channel from which the respective light is output is the same,
which should not be construed as limitation.
[0073] The above embodiments are only the preferred embodiments of
the present invention, and are not intended to limit the scope of
the present invention. All the equivalent structures made by taking
advantages of the specification and the drawings of the present
invention or those directly and indirectly applied to other related
technical fields are included in the protection scope of the
present invention.
* * * * *